The invention relates to the field of connecting tubular bodies together to form a confined passage. The specific field of the invention relates to the connection of tubular bodies such as pipes. In the detailed exemplary description to follow, the invention is described for connecting together underwater pipelines, J-tubes and other submerged bodies.
Joining together submerged pipelines has presented special problems because conventional welding techniques and other conventional joining procedures cannot be employed underwater. If conventional welding is to be attempted, an evacuated chamber must be positioned around the area to be welded. These chambers are difficult to manage and in some cases their use is either impractical or impossible.
A variety of mechanical connectors have been employed in an attempt to secure the ends of pipelines together below the surface of the water. These devices are secured to the pipeline ends by mechanical gripping means, in some cases with the use of elastomers or adhesives and by a variety of other means. The resulting joint is frequently unreliable because the mechanical means slip, the elastomers fail and leak, the adhesives do not secure or the joint is improperly secured so that no seal is effected. To the extent that conventional connectors have required divers to perform complicated procedures and use clumsy tools, the devices have been unsatisfactory. While divers can perform simple procedures such as threading a nut onto a bolt, more complicated procedures are extremely difficult and time-consuming.
Any joint which has a restricted internal opening is undesirable because it is frequently desirable or necessary to run devices through the pipeline. For this reason, conventional connectors which require internal gripping devices and other means restricting the internal passage of the pipeline are unsatisfactory in many applications.
The problems of attempting to join submerged pipelines are compounded when the ends of the two lines are misaligned. In many cases, the ends of the pipelines cannot be shifted and it becomes necessary to connect the ends with a connector which can suitably accommodate the misalignment.
Generally, conventional underwater pipe connectors have been difficult and expensive to use and the joints made by such connectors have been prone to failure.